An Organic Light-Emitting Diode (OLED) display device is a display device with a self-light emitting function. An OLED display device includes a plurality of pixels arranged in a matrix form. OLED display devices can be categorized into Active Matrix Organic Light-Emitting Diode (AMOLED) display devices and Passive Matrix Organic Light-Emitting Diode (PMOLED) display devices based on driving modes of the pixels, where the AMOLED display device is widely used in the display industry due to its advantages, such as thinness, light weight, active light emission, fast response, wide viewing angle, rich colors, high brightness, low power consumption, high-temperature resistance and low-temperature resistance.
The AMOLED display device generally includes a display substrate. The display substrate includes a base substrate and a plurality of Thin Film Transistors (TFTs) disposed on the base substrate. The display substrate further includes a planarization layer, a pixel defining layer and a spacer pattern, which are sequentially disposed on the base substrate provided with a plurality of TFTs.
In the related art, a method for preparing a spacer pattern in a display substrate generally includes: coating a spacer material on a base substrate provided with a pixel defining layer to form a spacer layer, and exposing the base substrate coated with the spacer layer under ultraviolet light using a mask to form a spacer pattern.
However, in the related art, when a spacer pattern is prepared, the spacer material is generally an organic resin material and the thickness of the spacer layer is large, but the area of the spacer pattern is smaller and the area to be exposed is large; therefore, the exposure energy of the ultraviolet light required for exposing the spacer layer is large; and when the ultraviolet light reaches an active layer in TFTs, the characteristics of the TFTs may drift (i.e., magnitudes of threshold voltages of multiple TFTs may vary), affecting the threshold voltages of the TFTs. When an image is displayed, if the multiple TFTs are loaded with the same voltage, since the threshold voltages of the TFTs are different, currents passing pixels corresponding to the multiple TFTs are also different, resulting in uneven brightness of the pixels on the display device and affecting the image display stability of the display device.